A refrigerator apparatus that includes a compressor apparatus for compressing a refrigerant such as a helium and a cryogenic refrigerator is known. According to the refrigerator apparatus, a gas heat exchanger is used and a plurality of cooling fans are provided such that a fan with a lower cooling capability is allocated to a heat exchanger pipe for a high pressure helium gas and a fan with a higher cooling capability is allocated to a heat exchanger pipe for a refrigerator oil, thereby increasing cooling efficiency.
However, according to such a compressor apparatus, because there are a plurality of cooling fans, mechanical and electrical losses are increased such that more electric power is required for cooling with, respect to a configuration in which a single fan is used. In particular, with respect to a configuration in which a single large fan is provided in a space for the fans, a total volume of air is reduced, which reduces cooling efficiency.
Further, a pressure loss characteristic curve under a condition of a static pressure becomes greater in the case of using the fans instead of a single large fan, which reduces the volume of air and thus the cooling efficiency. Further, in the case of using the fans, a number of parts is increased, and a cost is increased due to an increase in a failure rate as well as running cost.